The present invention relates to a power controller for peripheral devices in a computer system utilizing a software switch.
In prior art, various mechanical switches have been used for computer peripheral devices such as monitors. The mechanical switch is disadvantageous in consumption of parts caused by frequent use and in operational and mcchanical deficiencies, whereby the mechanical switch may fail. If the mechanical switch fails, the computer peripheral device such as monitor becomes inoperable.
As the main switch, a software switch has been proposed. The software switch detects whether or not the switch is pushed down instantly. It is therefore sufficient that the switch is instantly pushed down for allowing the software switch to detect an instant contact. This is advantageous in avoidance of the failure of the switch.
When the software switch is used as the main switch for the monitor, it is necessary to do power ON of a main power switch for the software switch. In a software switch, power is always supplied through a power cable to a CPU as a part of the software switch, so that the CPU is always in operable state. The power supplies to the other parts than the software switch are under the control of the CPU.
This software switch in use of the main power switch for the monitor is incapable of doing what the mechanical switches can do. The mechanical switch allows that the power cable of the monitor is plugged into a socket of the computer so that the main switch of the monitor is left in an ON state, whereby switching ON the main power switch of the computer causes an automatic switching ON of the monitor. By contrast to the mechanical switch, the software switch in use for the main power switch for the monitor subjects the power supply to the other parts of the software switch to strict control of the CPU, for which reason even if the power cable of the monitor is plugged into a socket of the computer, then there is the problem that the ON/OFF operation of the monitor power supply is associated with ON/OFF operation of the computer.
Various peripheral devices are connected to the advanced computer system and the same number of the switches as the peripheral devices are required. It is of course convenient for users that a single switch is effective for power ON to all of the peripheral devices.
In the above circumstances, it bad been required to develop a power controller for a software switch.